Hi
I work with 2015 iMac's , i Repair and upgrade them and the retina LCD's will ALL go pink. I have observed this in the 2015,2017 and the 2019 models 27" and 21.5". This is an issue which apple have not gotten past on those models, i'm not sure about the 2020 as i have not had a pink one on the bench yet or the 2021's. A friend of mine recently purchased a 27" 2019 and i simply advised him to sell it on before 3 years are up otherwise there would be the first signs of the pink hue appearing. If you are in a fortunate enough position to be able to get a new mac on release then this need not bother you, however if like me those kinds of purchases are treats and only occur every now and then i would say go with a non retina option otherwise you WILL end up with a pink LCD.